There are many inherent risks that come along with being a politician. As we've already seen from Robert Kennedy, John F. Kennedy and Abraham Lincoln on this list, one of those risks is that someone may wish to assassinate you. The risk of this increases significantly if you're trying to introduce liberal policies into a conservative environment. In the case of Benazir Bhutto, she was trying to do precisely that while also a woman in a political system controlled by men. Shortly after announcing that she would soon be campaigning for the Presidency of Pakistan, she was killed in a car bombing incident in December 2007.
This image was taken moments before the fatal bombing, and seems to demonstrate multiple issues with security around the event. People were allowed far too close to the car, and there's no evidence of a strong police or security presence. It's widely believed that Islamic fundamentalists carried out the attack.